1. Naep note: Problem solving;Carpenter;The Mathematics Teacher,1980
2. How children solve simple word problems;Carpenter;Education and Urban Society,1985
3. Mathematics counts: Report of the committee of inquiry into the teaching of mathematics in schools;Cockcroft,1982
4. Teaching mathematics in the elementary school;Collier,1969
5. Problem solving: The third dimensions in mathematics teaching;Gadanidis;The Mathematics Teacher,1988